CN1670508A - Optical image measuring apparatus - Google Patents

Abstract

An optical image measuring apparatus capable of effectively obtaining a direct current component of a heterodyne signal which is composed of background light of interference light is provided. The optical image measuring apparatus includes: an optical interference system in which a light beam from a light source is divided into signal light and reference light by a beam splitter, a frequency of the reference light is shifted by a frequency shifter, and the signal light propagating through an object to be measured and the reference light reflected on a mirror are superimposed on each other by the beam splitter to produce interference light; beam splitters for dividing the interference light into interference light beams; shutters serving as an intensity modulating unit for modulating intensities of the respective interference light beams at predetermined intervals; CCDs for receiving the respective interference light beams whose intensities are modulated and outputting electrical signals; and a signal processing portion serving as a calculating unit for calculating an intensity of the direct current component corresponding to the background light of the interference light based on the outputted electrical signals.

Description

Optical image-measuring device

Technical field

The present invention relates to a kind of determined object illumination beam to the light scattering medium, and utilize its reflected light or transmitted light that the configuration of surface and the external morphology of determined object are carried out instrumentation, and form the optical image-measuring device of its image, particularly relate to a kind of optical heterodyne detection method of utilizing the configuration of surface and the external morphology of determined object carried out instrumentation, and form the optical image-measuring device of image.

Background technology

In recent years, utilize the surface of the determined objects of formation such as LASER Light Source and the optical image-measuring technology of the image of inside to concentrate gazing at of people.This optical image-measuring technology is expected so its application aspect medical field is carried out especially because do not have the existing known X ray CT (computer tomography, CT Scan) of picture like that to the harmfulness of human body.

As an example of the exemplary process of light image detection technique, a kind of low relevant (coherence) interferometric method (being also referred to as light coherence tomography image conversion method etc.) is arranged.This method is utilized for example super-radiance light emitting diode (Super Luminescent Diode; SLD) the low interference capability of such broadband light source with wide spectrum (spectrum) width, and can be to reflected light and the transmitted light from determined object, detect (reference example non-patent literature 1 described as follows) with the good of μ m level apart from capacity of decomposition.

As an example of the device that has utilized this low coherence interference method, as shown in Figure 8 according to the basic comprising of the existing known optical image-measuring device of Mike inferior (Michelson) interferometer.The formation of this optical image-measuring device 100 comprises broadband light source 101, mirror 102, optical splitter 103 and photodetector 104.Determined object 105 is formed by scattering medium.The light beam that broadband light source 101 is sent, by optical splitter 103 be split into towards mirror 102 with reference to light R with towards the flashlight S of determined object 105 two parts.With reference to light R is the reflected light that utilizes optical splitter 103, and flashlight S is the transmitted light of optical splitter 103.

Here, as shown in Figure 8, on the direct of travel of flashlight S, be set at the z axle, and will be defined as the x-y face the orthogonal face of the direct of travel of flashlight S.Mirror 102 can be along carrying out displacement with the both sides flechette-type symbol directions (z-direction of scanning) among the figure.

On being reflected to mirror 102 time, accept multispectral reining in (Doppler) frequency shifting with reference to light R by this z-scanning.On the other hand, flashlight S is on shining determined object 105 time, and flashlight S is reflected on its surface and interior layer.Because determined object is a scattering medium, so can think that the reflected light of flashlight S is the diffusion corrugated with mixed and disorderly phase place of multiple scattering.Via the flashlight of determined object 105 and via mirror 102 and accepted frequency shifting with reference to light, to utilize optical splitter 103 to carry out overlapping and to generate interference light.

In utilizing the image instrumentation of low coherence interference method, have only flashlight S and just can produce interference to the coherent length (but interference distance) of 10 μ m levels with interior in several μ m levels of wideband territory light source 101 with reference to the optical path length difference of light R.That is, just the coherent signal light component of flashlight S is interfered mutually with reference light R selectively.According to this principle, by the position of mirror 102 being carried out z-scanning the optical path length with reference to light R is changed, can measure the light reflectance profile (profile) of the interior layer of determined object 105.By the scanning of carrying out this z direction and x-y face direction, and utilize photodetector 104 to detect interference light.Electric signal (heterodyne signal) output from photodetector 104, the colour wheel exterior feature (backscatter profile) that looses behind the interior layer of determined object 105 is provided, 2 dimension faultage images of determined object 105 scan by the signal S to the determined object 105 of crosscut and generate, on each opposite location that generates, recording light reflectance profile (with reference to non-patent literature 1).

In addition, as establish and utilize optical splitter 103 to carry out overlapping intensity to be respectively I with reference to light R and flashlight S _rAnd I _s, and difference on the frequency and the phase differential established between two light waves are respectively f _IfAnd Δ θ, the then heterodyne signal (for example with reference to non-patent literature 2) that is shown below from photodetector output.

[several 1]

$i\left(t\right)\∝I_r+I_s+2\sqrt{I_r{I}_s}\cos (2\mathrm{\π}{f}_{\mathrm{if}}t+\mathrm{\Δ\θ})---\left(1\right)$

The 3rd on the right of formula (1) is an ac signal, its frequency f _IfEqual beat (beat claps) frequency with reference to light R and flashlight S.The frequency f of the alternating component of heterodyne signal _IfBe known as bat rate etc.And the 1st and the 2nd on the right of formula (1) is the flip-flop of heterodyne signal, and corresponding with the signal intensity of the bias light of interference light.

But, obtain 2 dimension faultage images in order to utilize this existing known low coherence interference method, by the reflectance profile at determined object 105, sweep signal light S has needs, and then the reflecting light that detects successively from each opposite location needs.Therefore, need the long time, and consider that its instrumentation principle can find, be difficult to seek the shortening of instrumentation time for the determined object 105 of instrumentation.

In view of these problems, studied a kind of optical image-measuring device that is used to shorten the instrumentation time.Figure 9 shows that the basic comprising of an example of this device.Formation with the optical image-measuring device shown in the figure 200 comprises broadband light source 201, mirror 202, optical splitter 203, ties up optical sensor array 204 and lens 206,207 as 2 of photodetector.From the emitted light beam of light source 201, form parallel beam by lens 206,207, and its wave beam is directly enlarged, and utilize optical splitter 203 and it is divided into reference to light R and flashlight S two parts.Paid with the doppler frequency displacement by the z-scanning of mirror 202 with reference to light R.On the other hand, flashlight S since its wave beam directly enlarge, so can the x-y face on a large scale in the determined object 205 of incident.By this, flashlight S formation contains the surface of the determined object 205 in this incident scope and the reflected light of the information of inside.It is overlapping to utilize optical splitter 203 to carry out with reference to light R and flashlight S, and utilizes the assembly (optical sensor) of institute's mounting arranged side by side on 2 dimension optical sensor arrays 204 to detect.Therefore, can light beam not scanned, tie up faultage images and obtain 2 of determined object 205 in real time.

As the optical image-measuring device of this non-sweep type, the known device that has a kind of non-patent literature 3 to be recorded and narrated.In the device of recording and narrating with document, a plurality of heterodyne signals of being exported from 2 dimension optical sensor arrays can be imported the signal processing system of configuration side by side, and the amplitude and the phase place of each heterodyne signal detected.

But, in order to improve the spatial decomposition ability of image, must increase the package count of array, in addition, must prepare to have the signal processing system of counting with the corresponding channel of this package count (channel).Therefore, it is considered to be difficult to carry out practicability on fields such as the medical treatment of the image that needs the high de-agglomeration ability and industry.

Therefore, present inventors have proposed a kind of optical image-measuring device of following such non-sweep type in following patent documentation 1.Optical image-measuring device about this motion comprises: light source is used for outgoing beam; Interference optics, be used for the light beam that this light source is emitted and be divided into flashlight via the detected body allocation position that disposes detected body, with via with aforementioned via the different light path of the light path of detected body allocation position with reference to light two parts, and will be via the flashlight behind the aforementioned detected body allocation position, with via aforementioned different light path carry out overlappingly each other with reference to light, and generate interference light; The frequency shifting device is used for the aforementioned signal light frequency of this interference optics is carried out displacement with aforementioned with reference to light frequency is relative; The light masking device, aforementioned interference optics cuts apart by aforementioned interference light is carried out two in order to accept aforementioned interference light, this is periodically covered by two interference lights of having cut apart, and the phase differential that generates each other is 2 row interference light pulses of 90 degree again; Optical sensor is accepted aforementioned 2 row interference light pulses respectively; Signal processing part, this optical sensor has a plurality of light-receiving modules that light signal was arranged and obtained independently respectively being subjected to spatiality, and the resulting a plurality of light signals that are subjected to of aforementioned lights sensor are merged, and the surface or the interior layer of the detected body that is disposed on generation and the aforementioned detected body allocation position, and corresponding signal of each care point on the transmission path of aforementioned flashlight.

This optical image-measuring device adopts the interference light with reference to light and flashlight to carry out two to cut apart, and is subjected to light with 2 optical sensors (2 dimension optical sensor array), and disposes the light masking device before the two sensors array respectively, with the formation that interference light is sampled.And, can be by the phase differential that pi/2 was set in the sampling period of divided 2 interference lights, and detect to the flashlight of the bias light that constitutes interference light with reference to the orthogonal composition (sin composition and cos composition) of the phase place of light intensity and interference light, and by included background light intensity in will output from the two sensors array, from the output of two sensors array, remove, and 2 phase place orthogonal compositions of calculating interference light, and utilize this result of calculation to try to achieve the amplitude of interference light.

In utilizing this optical image-measuring device, the flip-flop of the heterodyne signal of the bias light of corresponding interference light is necessary to try to achieve in its mode.Specifically, dimmer is made as open state, accepts interference light continuously,, try to achieve flip-flop by this to calculate the time average that is subjected to the light result.But, do not disclose about other adquisitiones is concrete, so the degree of freedom of instrumentation kenel is little,, must consider the scheme of other instrumentation kenel in order to improve the degree of freedom of operability or apparatus structure.

In addition, the inventor proposes a kind of optical image-measuring device in patent shelves 2, and it has light source, interference optics, frequency shift device and optical devices.Light source is used for outgoing beam, interference optics is used for the light beam with this light source outgoing, two are divided into the flashlight via the allocation position of object to be detected, and through the light path different with the light path of the allocation position of object to be detected with reference to light, by generating aforementioned flashlight and aforementioned interference light through the overlapping each other of aforementioned different light path with reference to light with reference to the interference of light; Aforementioned interference optics, frequency shift device make aforementioned signal light frequency and aforementioned with reference to light frequency displacement relatively; Aforementioned interference optics, optical devices be aforementioned flashlight and aforementioned with reference to one of them light path in the light on, photoperiodism ground is covered.The frequency of covering of aforementioned optical devices equals aforementioned flashlight and aforementioned with reference to the difference on the frequency between the light.According to this optical image-measuring device,, can seek to realize that heterodyne is measured preferably because the available blocking frequency that equals beat frequency comes interference light is sampled.

Also have in this optical image-measuring device and need go to measure the flip-flop that bias light was constituted by interference light in other mode, specifically, it is opened and shows a kind of method, with phase deviation π and pi/2, carry out 2 sampling, this measurement result is applied calculation handle, to calculate this flip-flop.But identical with the problem points of patent shelves 1, it is preferable utilizing other method also can calculate this flip-flop.

In addition, as the mensuration of the other mode of the optical image-measuring device that do not look like patent shelves 1,2, can try to achieve the flip-flop that bias light constitutes according to instrumentation once, the trouble of instrumentation can alleviate, and the instrumentation time also can shorten.But, in the optical image-measuring device that these patent documents are put down in writing, realize it also being difficult.

Moreover, in these patent documents, work period when not considering the sampling interference light is than (dutyratio) or (patent document 1 for use the function of " rectangle ") such as feature items relevant with the waveform of sampling function, but in order to improve the degree of freedom of instrumentation kenel, or in order to realize instrumentation more efficiently, these items also should spend the time to go to consider.In addition, also only mention the situation that equates in beat frequency, provide degree of freedom more diversified and raising sampling kenel on device is used, to be considered to be necessary about sampling function.

The spy of [patent documentation 1] Japanese Patent Laid Open Publication opens 2001-330558 communique (claim item, paragraphs [0044], [0072]-[0077], the 1st figure, the 3rd figure)

The 32451 No. 35 communique of [patent documentation 2] Jap.P. (claim item, paragraphs [0072]-[0082], the 1st figure, the 3rd figure)

No. the 3rd, [non-patent literature 1] red wild straight great " optics " (Japanese optics magazine) the 28th volume, 116 (1999)

Compile in [non-patent literature 2] Ji Ze, rapids field, and " light heterodyne technology (revised edition) ", new technology communication (2003), p.2

[non-patent literature 3] K.P.Chan, M.Yamada, H.Inaba, [ElectronicsLetters], Vol.30,1753, (1994)

This shows that above-mentioned existing optical image-measuring device obviously still has inconvenience and defective, and demands urgently further being improved in structure and use.In order to solve the problem that optical image-measuring device exists, relevant manufacturer there's no one who doesn't or isn't seeks solution painstakingly, but do not see always that for a long time suitable design finished by development, and common product does not have appropriate structure to address the above problem, and this obviously is the problem that the anxious desire of relevant dealer solves.Therefore how to found a kind of optical image-measuring device of new structure, just become the current industry utmost point to need improved target.

Because the defective that above-mentioned existing optical image-measuring device exists, the inventor is based on being engaged in this type of product design manufacturing abundant for many years practical experience and professional knowledge, and the utilization of cooperation scientific principle, actively studied innovation, in the hope of founding a kind of optical image-measuring device of new structure, can improve general existing optical image-measuring device, make it have more practicality.Through constantly research, design, and after studying sample and improvement repeatedly, create the present invention who has practical value finally.

Summary of the invention

The objective of the invention is to, overcome the defective that existing optical image-measuring device exists, and provide a kind of optical image-measuring device of new structure, technical matters to be solved is to make it can try to achieve flip-flop by the heterodyne signal that bias light constituted of interference light effectively, thereby is suitable for practicality more.

Another object of the present invention is to, a kind of optical image-measuring device is provided, technical matters to be solved is to make its degree of freedom by the sampling kenel that improves interference light, promotes practicality, thereby is suitable for practicality more.

The object of the invention to solve the technical problems realizes by the following technical solutions.In order to reach the foregoing invention purpose, first invention of the present invention provides a kind of optical image-measuring device, have light source and interference optics, wherein light source is used for outgoing beam, interference optics is used for the light beam from this light source, be divided into via the flashlight of object to be detected and via set with reference to object with reference to light, and make aforementioned signal light frequency with aforementioned with reference to light frequency is relative carry out displacement after, make via aforementioned object to be detected aforementioned flashlight and via aforementionedly carrying out overlapping each other with reference to light with reference to the aforementioned of object, and the generation interference light, and this optical image-measuring device forms the image of aforementioned determined object according to aforementioned interference light.Optical image-measuring device is characterised in that and comprises the intensity modulation device, with the predetermined aforementioned interference light intensity of frequency modulating; Optical detection device is accepted by the aforementioned interference light of aforementioned intensity modulation, is transformed into electrical signal and with its output; And calculation apparatus, according to the aforementioned electrical signal from aforementioned optical detection device output, calculation is by the intensity of the flip-flop that bias light constituted of aforementioned interference light.

The object of the invention to solve the technical problems also realizes by the following technical solutions.Again, in order to reach the foregoing invention purpose, second invention of the present invention provides a kind of optical image-measuring device, has light source, interference optics and beam-divider means, and wherein light source is used for outgoing beam; Interference optics is used for the light beam from this light source, be divided into via the flashlight of object to be detected and via set with reference to object with reference to light, and make aforementioned signal light frequency with aforementioned with reference to light frequency is relative carry out displacement after, make via aforementioned object to be detected aforementioned flashlight and via aforementionedly carrying out overlappingly each other with reference to light with reference to object aforementioned, and generate interference light; The aforementioned interference light that beam-divider means generates aforementioned interference optics is divided into most light paths, and wherein this optical image-measuring device forms the image of aforementioned determined object according to the aforementioned interference light that transmits in an aforementioned majority light path.Optical image-measuring device is characterised in that and comprises: most intensity modulation devices are separately positioned on the wherein several light path in the aforementioned majority light path, with the predetermined aforementioned interference light intensity of frequency modulating; A most optical detection device, be separately positioned on the aforementioned majority light path, the aforementioned lights pick-up unit that wherein is arranged on wherein several light paths of an aforementioned majority light path is to accept by the aforementioned interference light of aforementioned intensity modulation, be transformed into electrical signal and with its output, and be arranged on aforementioned lights pick-up unit beyond wherein several light paths of an aforementioned majority light path for accepting aforementioned interference light, be transformed into electrical signal and with its output; And calculation apparatus, according to the aforementioned electrical signal that the aforementioned lights pick-up unit on the predetermined light paths from be arranged on an aforementioned majority light path is exported, calculation is by the intensity of aforementioned flip-flop.

At this, so-called " several light path ", any number in the light path of aforementioned majority (being made as N), that is the light path of any one number of 1～N.

Moreover, in order to achieve the above object, according to the 3rd invention of the present invention, for aforementioned predetermined light paths in second invention comprises at least two light paths that aforementioned intensity modulation device is set up, aforementioned intensity modulation device on aforementioned at least two light paths is the aforementioned interference light of modulation respectively, the phase differential that makes aforementioned lights pick-up unit on this light path accept aforementioned interference light is the part of π (180 degree), and aforementioned calculation apparatus carries out time average by the aforementioned electrical signal that the aforementioned lights pick-up unit is exported, and calculates out the intensity of aforementioned flip-flop.

In addition, in order to achieve the above object, according to the 4th invention of the present invention, for aforementioned predetermined light paths in second invention comprises the light path that aforementioned intensity modulation device is not set up, aforementioned calculation apparatus carries out time average by the aforementioned electrical signal that the aforementioned lights pick-up unit is exported, and calculates out the intensity of aforementioned flip-flop.

In addition, in order to achieve the above object, according to the 5th invention of the present invention, for aforementioned intensity modulation device in first or second invention carries out majority time intensity modulation to aforementioned interference light, the phase differential that makes the aforementioned lights pick-up unit accept aforementioned interference light is the part of π.The aforementioned lights pick-up unit is accepted and the inferior corresponding aforementioned interference light of each time intensity modulation of aforementioned majority, the output electrical signal.The corresponding aforementioned several intensity modulation of aforementioned calculation apparatus carries out time average by the aforementioned electrical signal that the aforementioned lights pick-up unit is exported, and calculates out the intensity of aforementioned flip-flop.

In addition, according to the 6th invention of the present invention, for aforementioned intensity modulation device in first or second invention is to utilize not and the synchronous frequency beat period of aforementioned interference light, aforementioned interference light is carried out intensity modulation, and aforementioned calculation apparatus is according to the aforementioned interference light of doing the intensity modulation with this frequency, carry out time average by the aforementioned electrical signal that the aforementioned lights pick-up unit is exported, calculate out the intensity of aforementioned flip-flop.

In addition, in order to achieve the above object, according to optical image-measuring device of the present invention, the 7th invention of the present invention provides a kind of optical image-measuring device, have light source and interference optics, wherein light source is used for outgoing beam, interference optics is used for the light beam from this light source, be divided into via the flashlight of object to be detected and via set with reference to object with reference to light, and make aforementioned signal light frequency with aforementioned with reference to light frequency is relative carry out displacement after, make via aforementioned object to be detected aforementioned flashlight and via aforementionedly carrying out overlapping each other with reference to light with reference to the aforementioned of object, and the generation interference light, and this optical image-measuring device forms the image of aforementioned determined object according to aforementioned interference light.Optical image-measuring device is characterised in that and comprises: the intensity modulation device, with the predetermined aforementioned interference light intensity of frequency modulating; Optical detection device is accepted by the aforementioned interference light of aforementioned intensity modulation, is transformed into electrical signal and with its output; And calculation apparatus, according to the aforementioned electrical signal from aforementioned optical detection device output, calculation is by the intensity of the flip-flop that bias light constituted of aforementioned interference light, and the intensity and/or the phase place of calculation alternating component.

In addition, in order to achieve the above object, according to optical image-measuring device of the present invention, according to the 8th invention of the present invention, the 7th invention more comprises a light-receiving time switch means, the cycle of the beat frequency of corresponding aforementioned interference light, the light-receiving time of the aforementioned interference light of aforementioned lights pick-up unit is switched between one first light-receiving time and one second light-receiving time, wherein aforementioned first light-receiving time has the above length of cycle of aforementioned beat frequency, and aforementioned second light-receiving time has the length less than the cycle of aforementioned beat frequency.Wherein aforementioned calculation apparatus is former when stating the light-receiving time switching device shifter and switching to aforementioned first light-receiving time, carry out time average by the electrical signal that the aforementioned lights pick-up unit is exported, calculate out the intensity of aforementioned flip-flop, and when switching to aforementioned second light-receiving time, the aforementioned electrical signal of being exported according to the aforementioned lights pick-up unit, and corresponding aforementioned first light-receiving time and the aforementioned flip-flop calculated out, calculate out the intensity and/or the phase place of aforementioned alternating component.

In addition, in order to achieve the above object, according to optical image-measuring device of the present invention, according to the 9th invention of the present invention, aforementioned light-receiving time switching device shifter switches aforementioned light-receiving time with the cycle of the beat frequency of every aforementioned interference light in the 8th invention, and aforementioned first light-receiving time is aforementioned beat period.

In addition, in order to achieve the above object, according to optical image-measuring device of the present invention, according to the tenth invention of the present invention, aforementioned light-receiving time switching device shifter switches aforementioned light-receiving time with the cycle of the beat frequency of every aforementioned interference light in the 8th invention, and aforementioned second light-receiving time is half of aforementioned beat period.

In addition, in order to achieve the above object, according to optical image-measuring device of the present invention, according to the 11 invention of the present invention, the aforementioned preset frequency that aforementioned intensity modulation device carries out intensity modulation to aforementioned interference light in the 7th invention is the frequency of integral multiple of the beat frequency of aforementioned interference light.

In addition, in order to achieve the above object, according to optical image-measuring device of the present invention, according to the 12 invention of the present invention, in any one first to the 7th invention, aforementioned intensity modulation device is the dimmer device, with aforementioned predetermined frequency, interdict aforementioned interference light.

According to optical image-measuring device of the present invention, because comprise the intensity modulation device, with the predetermined aforementioned interference light intensity of frequency modulating; Optical detection device is accepted by the aforementioned interference light of aforementioned intensity modulation, is transformed into electrical signal and with its output; And calculation apparatus, according to the aforementioned electrical signal from aforementioned optical detection device output, calculation is by the intensity of the flip-flop that bias light constituted of aforementioned interference light, so can try to achieve the flip-flop that bias light constituted of interference light effectively.

According to the optical image-measuring device of the 3rd to the 6th invention,,, obtain flip-flop effectively so can install set optical detection device in response to this because the electrical signal that can export according to one or two optical detection device is tried to achieve flip-flop.

Particularly according to the optical image-measuring device of the 4th invention, because can try to achieve flip-flop, so can seek the simplification of apparatus structure according to the electrical signal exported of optical detection device on the light path that not have setting from the intensity modulation device.

In addition, the words of the 8th to the tenth optical image-measuring device that name is put down in writing according to the present invention, light-receiving time corresponding to the interference light of optical detection device is switched to first light-receiving time, calculate flip-flop effectively, moreover, light-receiving time corresponding to the interference light of optical detection device is switched to second light-receiving time, uses the result of calculation of above-mentioned flip-flop, calculates alternating component.Therefore, for example at the depth direction of determined object while scanning (z-scanning) when carrying out the situation of instrumentation, if use this optical image-measuring device, because the value of the flip-flop that calculates before can using, try to achieve alternating component in regular turn, stock trick is surveyed precision and can be promoted.

In addition, the optical image-measuring device that the 11 invention is put down in writing according to the present invention because use various frequencies to carry out the sampling of interference light, can improve the degree of freedom of structure.

The present invention compared with prior art has tangible advantage and beneficial effect.Via as can be known above-mentioned, the invention relates to a kind of optical image-measuring device, can try to achieve flip-flop effectively by the heterodyne signal that bias light constituted of interference light.Optical image-measuring device 1 comprises interference optics, to be divided into flashlight S with optical splitter 5 from the light beam of light source 2 and with reference to light R, and utilize frequency shifting device 6 to make and carry out displacement with reference to the frequency of light R, and make through the flashlight S of determined object O and by mirror 7 reflect overlapping with reference to light R, generate interference light L; Optical splitter is used for interference light is divided into interference light L1, L2, L3; Dimmer 31,32,33 is for carrying out the intensity of each interference light L1, L2, L3 the intensity modulation device of modulation with certain cycle; CCD 21,22,23, accept each interference light of intensity modulation, and the output electrical signal; And signal processing part 60, according to the electric signal of output, calculating is corresponding to the intensity of the flip-flop of the bias light of interference light L.

In sum, the optical image-measuring device of special construction of the present invention can be tried to achieve the flip-flop by the heterodyne signal that bias light constituted of interference light effectively.The optical image-measuring device of special construction of the present invention, it promotes practicality by the degree of freedom of the sampling kenel that improves interference light.It has above-mentioned many advantages and practical value, and in like product, do not see have similar structural design to publish or use and really genus innovation, no matter it all has bigger improvement on apparatus structure or function, have large improvement technically, and produced handy and practical effect, and more existing optical image-measuring device has the multinomial effect of enhancement, thus be suitable for practicality more, and have the extensive value of industry, really be a new and innovative, progressive, practical new design.

Above-mentioned explanation only is the general introduction of technical solution of the present invention, for can clearer understanding technological means of the present invention, and can be implemented according to the content of instructions, and for above-mentioned and other purposes, feature and advantage of the present invention can be become apparent, below especially exemplified by preferred embodiment, and conjunction with figs., be described in detail as follows.

Description of drawings

Figure 1 shows that skeleton diagram about an example of the formation of optical image-measuring device of the present invention.

Figure 2 shows that a example about the sampling form of the interference light of optical image-measuring device of the present invention.Fig. 2 (A) is depicted as the plot of the time waveform of interference light.Fig. 2 (B) is depicted as the plot of an example of the waveform of sampling function.Fig. 2 (C) is depicted as the plot of the waveform of the interference light of being sampled.

Figure 3 shows that plot about an example of the formation of the variation example of optical image-measuring device of the present invention.

Figure 4 shows that plot about an example of the formation of the variation example of optical image-measuring device of the present invention.

Figure 5 shows that plot about an example of the formation of the variation example of optical image-measuring device of the present invention.

Figure 6 shows that skeleton diagram about an example of the formation of the variation example of optical image-measuring device of the present invention.

Figure 7 shows that plot about an example of the formation of the variation example of optical image-measuring device of the present invention.

Figure 8 shows that the skeleton diagram of the formation that has known optical image-measuring device now.

Figure 9 shows that the skeleton diagram of the formation that has known optical image-measuring device now.

1: optical image-measuring device

2: broadband light source 3,4: lens

5,11,12: optical splitter 6: the frequency shifting device

6 ': piezoelectric element 7,10: mirror

8: imaging lens group 21,22,23:CCD (charge-coupled image sensor)

31,32,33: dimmer 41,42,43: phase-shifted device

50: pulse signal generator 60: signal processing part

100,200: optical image-measuring device 101,201: broadband light source

R: with reference to light S: flashlight

L, L1, L2, L3: interference light O: determined object

Embodiment

Reach technological means and the effect that predetermined goal of the invention is taked for further setting forth the present invention, below in conjunction with accompanying drawing and preferred embodiment, to its embodiment of optical image-measuring device, structure, feature and the effect thereof that foundation the present invention proposes, describe in detail as after.

Below, an example to about the example of optical image-measuring device of the present invention at length describes with reference to icon.

About optical image-measuring device of the present invention, to be frank, in order to obtain effectively via the flashlight of determined object and intensity with reference to the flip-flop that bias light constituted of interference of light light via the reference object, possesses a kind of structure, to interfere periodically modulation of light intensity, accept this interference light and output as electrical signal (heterodyne signal),, calculate out the intensity of its flip-flop according to this heterodyne signal.In addition, light image device of the present invention is used the characteristic in the hope of interference light for effective various sampling kenel is provided.As the characteristic of this interference light, comprise the signal strength of the flip-flop shown in for example above-mentioned formula (1), interference light and the space distribution of phase place etc.

Below, the optical image-measuring device of embodiments of the invention is described, it possesses a structure can be divided into the light path of interference light three, receives each interference light, according to the heterodyne signal of gained, by the signal strength of the intensity of the flip-flop that bias light constituted, interference light with and space distribution.But according to the adquisitiones of flip-flop and sampling kenel, the light path of interference light does not need to be divided into 3, and example as described below can be suitable the adopts interference light not cut apart, be divided into two or be divided into the structure of the light path more than four.

(formation of device)

Figure 1 shows that as about optical image-measuring device of the present invention it adopts the summary of the optical image-measuring device 1 that interference light is divided into 3 light paths and measures to constitute.This optical image-measuring device 1 is for being used in the device of for example medical aspect and industrial aspect, and it has the formation of the 2 dimension faultage images of each degree of depth (z direction) that can obtain the determined object O that is made of scattering medium.

Optical image-measuring device 1 is identical with existing known device, comprise the continuous light that output is low relevant the broadband light source 2 by super-radiance light emitting diode (SLD) or light emitting diode (LED) formation of etc.ing, will form parallel beam from the light beam of this light source 2 and enlarge its wave beam lens 3 directly, 4, light beam is divided into flashlight S and, and carries out them overlapping and generate the optical splitter 5 of interference light L and the mirror 7 that constitutes by completely reflecting mirror with reference to light R.And, near mirror 7, dispose the frequency shifting device 6 that constitutes by electrooptical modulator or acousto-optic formula modulator etc.In addition, the coherent length of the near-infrared region SLD that sells on the market is about 30 μ m, is being about 10 μ m under the situation of LED.In addition, though graphic omission is provided with drive unit, be used for making mirror 7 to move (z-scanning) toward travel direction with reference to light.

In addition, in the front of mirror 7, disposing the frequency shifting device 6 that is made of electrical equipment optic regulating device or sound equipment optic regulating device, the frequency with reference to light R that will pass through is carried out displacement.In addition, using by making mirror 7 do z-scanning, when reference light is given the situation of structure of Du Bule frequency shifting, do not needing frequency shifting device 6.But,, also frequency shifting device 6 and z-scanning can be merged in the situation that must increase with reference to the displacement (being beat frequency) of light frequency etc.

Here, lens 3,4, optical splitter 5, frequency shifting device 6 and mirror 7 constitute among the present invention said [interference optics].And mirror 7 constitutes " with reference to object " of the present invention.

And, in optical image-measuring device 1, be provided with the imaging that utilizes the interference light L that optical splitter 5 generates and carry out imaging and be divided into 3 interference light L1 with lens group 8, with this interference light L, L2, the optical splitter 11 of L3,12,2 dimension optical sensor arrays of the savings type of interference light detection usefulness are CCD (camera) 21,22,23 and be configured in these CCD near, by with interference light L1, the dimmer 31 that high speed dimmers such as the liquid crystal shutter that L2, L3 periodically cover respectively etc. are constituted, 32,33.

In addition, dimmer 31,32,33 there is no need to be separately positioned on CCD 21,22,23 near, the optional position that can link at the take-off point of the interference light L1, the L2 that utilize dimmer 11,12 to form, L3 on each light path of CCD 21,22,23 is provided with.That is, can cover each interference light L1, L2, L3 as long as dimmer 31,32,33 is configured in, and make utilize CCD 21,22,23 changed on 0 the position by the light light quantity to get final product.

Here, optical splitter 11,12 constitutes the present invention's said " light path segmenting device " optical splitter optical splitter respectively.In addition, CCD 21,22,23 constitutes the present invention's said " optical detection device ".And dimmer 31,32,33 constitutes " intensity modulation device " of the present invention and " dimmer ".

In addition, optical image-measuring device 1 comprises pulse signal producer 50, and it is used to produce pulse signal; And phase-shifted device 41,42,43, carry out displacement by its pulse signal that this pulse signal producer 50 is produced, and the clock signal that generates the switching sequence of independent respectively each dimmer 31,32,33 of the control line output of going forward side by side.

Each dimmer 31,32,33 is according to the clock signal from phase-shifted device 41,42,43, with cycle of setting respectively to cover interference light L1, L2, L3 samples.By this, each CCD 21,22,23 periodically accepts corresponding interference light L1, L2, L3, and as described later shown in Fig. 2 (C), interference light is subjected to light as periodic pulse train.At this moment, because each dimmer 31,32,33 independent switches respectively,, form the pulse of phase differential with setting so utilize interference light L1, the L2 that CCD 21,22,23 detects respectively, the pulse of L3.Interference light L1, the L2 that CCD 21,22,23 is detected each pixel (pixel), the intensity of L3 are carried out opto-electronic conversion, and are that electric signal (heterodyne signal) outputs to signal processing part 60 with its transformation result.Heterodyne signal is the interference light intensity that reflection detected and the electric signal of phase place.

Signal processing part 60 is carried out calculation process described later according to from CCD 21,22,23 heterodyne signals of being exported, and it is [arithmetic unit] of the present invention.In addition, signal processing part 60 is tieed up various images such as cross-section images by the result who resolves this calculation process and form 2 of determined object O, goes forward side by side and exercise its processing that shows on display equipment display device such as (not icons).Sort signal handling part 60 for example comprises having stored in formation sets the ROM (read-only memory) memory storages such as (ROM) of operation program and the formations such as computing machine of carrying out the central processing unit (CPU) of this operation program.

, and utilize optical splitter 5 and be divided into flashlight S and by lens 3 and lens 4 and its wave beam is directly enlarged from the emitted light beam of light source 2 with reference to light R.The determined object O of flashlight S incident, and as the reflecting light of the information that comprises its configuration of surface and external morphology and incident optical splitter 5 once more.

On the other hand,, after accepting frequency shifting, be sent to mirror 7 and be reflected with reference to light R by frequency shifting device 6.Its reflecting light is accepted further frequency shifting by frequency shifting device 6 once more, and incident optical splitter 5 once more.In addition, as previously mentioned, also can carry out z-scanning, make frequency shifting with reference to light R by making mirror 7.

Part from the flashlight S of determined object O is reflected via optical splitter 5, and the part with reference to light R of having accepted frequency shifting then sees through optical splitter 5.By this, flashlight S and overlapping by optical splitter 5 with reference to light R, and generate interference light L.This interference light L sees through imaging lens group 8, and is sent to optical splitter 11.

Interference light L utilizes optical splitter 11 and makes its light path be split into 2 parts.The interference light L1 that utilizes optical splitter 11 and be reflected is detected by CCD 21 by dimmer 31.

And, seen through the interference light of optical splitter 11, utilize next optical splitter 12 and its light path is cut apart by two once more.The interference light L2 that utilizes optical splitter 12 to be reflected is detected by CCD22 by dimmer 32.

On the other hand, seen through the interference light L3 of optical splitter 12, detected by CCD 23 by dimmer 33.

In addition, preferably make the segmentation rate of the interference light that utilizes optical splitter 11, the strength ratio of the interference light L1 of interference light that promptly sees through and reflection is 2: 1.That is, optical splitter 11 preferably has sees through 2/3 of incident light, and makes the characteristic of 1/3 reflection.And preferably making the strength ratio of interference light L3 that utilizes optical splitter 12 and be through and the interference light L2 that is reflected is 1: 1.That is, optical splitter 12 preferably has sees through 1/2 of incident light, and makes the characteristic of 1/2 reflection.By this, utilize CCD 21,22,23 and detected interference light L1, L2, the equal respectively strength grade (level) of L3 formation, so be fit to carry out calculation process described later.But the strength ratio of divided interference light is not limited thereto, and can take the circumstances into consideration to set.

[mensuration form]

Then, about the signal intensity of the interference light L that utilizes optical image-measuring device 1 and the space distribution of phase place, promptly the mensuration form of the intensity of heterodyne signal and phase information thereof describes.Optical image-measuring device 1 is characterised in that, by the switching sequence (timing) that utilizes dimmer 31,32,33, interference light L1, L2, the L3 that is paid with phase differential carried out sampling Detection, constitute intensity, the signal strength of interference light L and the space distribution of phase place of the flip-flop of bias light by one-shot measurement, and obtain the mistiming.

In addition, the phase differential of the sampling function described later of the switching sequence of responsible dimmer 31,32,33 need be set in advance.Sampling function is that phase- shifts device 41,42,43 makes the phase place of the pulse that is periodically taken place by pulse signal producer 50 produce displacement respectively, outputs to dimmer 31,32,33 and generates.

Fig. 2 is the key diagram that is used to illustrate the sampling action of the interference light L1 that utilizes dimmer 31.Fig. 2 (A) is depicted as the time waveform of utilizing optical sensor CCD 21 and being subjected to interference of light light L1.The heterodyne signal that utilizes interference light L1 is shown in above-mentioned formula (1), can consider it is the flip-flop that is constituted by the proportional bias light of intensity, and the alternating component (being also referred to as beat signal etc.) with beat frequency (beat frequency) of interference light L1 is overlapping person with reference light S and flashlight S.

Therefore, by according to the sampling function m shown in Fig. 2 (B) ₁(t) make dimmer 31 carry out periodically switch (on-off), and can sample interference light L1.Sampling function m ₁(t) rectangle that has by for example 50% work (duty) is listed as the waveform that is constituted, and makes this frequency f _SmBe set to and the beat frequency f shown in the formula (1) _IfEqual or the value close with it (is f _Sm=f _IfOr f _Sm f _If).

Fig. 2 (C) is depicted as and utilizes sampling function m ₁When (t) sampling, the time waveform synoptic diagram of the interference light L1 of incident CCD 21.Here, sampling function m ₁(t) frequency f _SmAnd the beat frequency f of the heterodyne signal shown in the formula (1) _IfPoor (δ f=|f _If-f _Sm|), be that the response frequency of CCD21 is compared with savings type optical sensor, be set enough for a short time.By this, can the part that phase place is roughly the same be sampled in each cycle of interference light L1.At this moment, from the output i of the CCD 21 that has accepted interference light L1 ₁(t), in minute with CCD 21 in the charge quantity of light put aside proportional, specifically, can obtain (for example with reference to M.Akiba, K.P.Chan, N.Tanno, [OpticsLetters], Vol.28,816 (2003)) by following formula.

[several 2]

$i_1\left(t\right)=<K_{1}i\left(t\right)m_1\left(t\right)>$

$=K_1[\frac{1}{2}{I}_s+\frac{1}{2}{I}_r+\frac{2}{\mathrm{\&pi;}}\sqrt{I_s{I}_r}\cos (2\mathrm{\&pi;\&delta;ft}+\mathrm{\&phi;})]---\left(2\right)$

Here,＜-expression is based on the time average of the savings effect of CCD 21.And φ represents the preliminary phase place value measured, K ₁Expression contains the light detection efficiency of the photoelectric conversion rate of the reflectivity of optical splitter 11 and CCD 21.

Similarly, utilize according to the sampling function m that sets ₂And utilize CCD 22 to detect (t) and 32 couples of interference light L2 of the dimmer of gauge tap sequential impose sampling.This sampling function m ₂(t), it has and the sampling function m that interference light L1 is sampled ₁(t) identical frequency f _Sm, i.e. the waveform of the rectangle of 50%duty row.Here, sampling function m ₂(t) to sampling function m ₁(t) has phase difference θ _1,2This phase difference θ _1,2By the phase place that makes pulse signal from pulse signal generator 50 shown in Figure 1, utilize phase-shifted device 42 and paid displacement.By above this condition, utilize and the same principle of formula (2), can obtain following such output i from CCD 22 ₂(t).

[several 3]

$i_2\left(t\right)=K_2[\frac{1}{2}{I}_s+\frac{1}{2}{I}_r+\frac{2}{\mathrm{\&pi;}}\sqrt{I_s{I}_r}\cos (2\mathrm{\&pi;\&delta;ft}+\mathrm{\&phi;}+\mathrm{\&Delta;}{\mathrm{\&theta;}}_{\mathrm{1,2}})]---\left(3\right)$

But, K ₂It is the light detection efficiency of the photoelectric conversion rate of the reflectivity of the transmitance that comprises optical splitter 11, optical splitter 12 and CCD 22.

By formula (2) and formula (3) as can be known, in output, include flashlight S respectively and with reference to the intensity I of light R from CCD 21,22 _s, I _rProject, about interference light L1, the amplitude  (I of L2 _sI _r) and phase place (2 π δ ft+ φ), (2 π δ ft+ Δ θ _1,2) project.

In addition, utilize according to sampling function m ₃And utilize CCD 23 to detect (t) and the dimmer 33 of gauge tap sequential imposes sampling to interference light L3.This sampling function m ₃(t), it has and the sampling function m that interference light L1 is sampled ₁(t) identical frequency f _Sm, i.e. the waveform of the rectangle of 50%duty row.Here, sampling function m ₃(t) to sampling function m ₁(t) has phase difference θ _1,3This phase difference θ _1,3By the phase place that makes from the pulse signal of pulse signal generator 50, utilize phase-shifted device 43 and paid displacement.At this moment, utilize and the same principle of formula (2), can obtain following such output i from CCD 23 ₃(t).

[several 4]

$i_3\left(t\right)=K_3[\frac{1}{2}{I}_s+\frac{1}{2}{I}_r+\frac{2}{\mathrm{\&pi;}}\sqrt{I_s{I}_r}\cos (2\mathrm{\&pi;\&delta;ft}+\mathrm{\&phi;}+\mathrm{\&Delta;}{\mathrm{\&theta;}}_{\mathrm{1,3}})]---\left(4\right)$

But, K ₃It is the light detection efficiency that comprises the photoelectric conversion rate of each transmitance of optical splitter 11,12 and CCD 23.

[calculation process]

Each CCD 21,22,23 electric signal of being exported from shown in formula (2), (3), (4) are sent to signal processing part 60.Signal processing part 60 is by utilizing these output result to carry out following illustrated computing, calculate the flip-flop of the heterodyne signal shown in the formula (1) of the bias light of corresponding interference light, and interference light L, the i.e. space distribution of the signal intensity of heterodyne signal and phase place.

Here, with sampling function m ₁(t) and sampling function m ₂(t) phase difference θ _1,2Be set at-pi/2, with sampling function m ₁(t) and sampling function m ₃(t) phase difference θ _1,3Be set at pi/2.At this moment, by the strength S of the flip-flop of the heterodyne signal that bias light constituted of interference light ₁And phase place orthogonal composition (sin composition and cos composition) S ₂And S ₃Represent by following formula respectively.

[several 5]

${\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">S</figure-callout>}}_1=\frac{i_2}{{\mathrm{<figure-callout\; id="2"\; label="K"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">K</figure-callout>}}_2}+\frac{i_3}{{\mathrm{<figure-callout\; id="3"\; label="K"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">K</figure-callout>}}_3}=I_s+I_r---\left(5\right)$

[several 6]

${\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">S</figure-callout>}}_2=\frac{i_2}{K_2}-\frac{i_3}{{\mathrm{<figure-callout\; id="3"\; label="K"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">K</figure-callout>}}_3}=\frac{4}{\mathrm{\&pi;}}\sqrt{I_s{I}_r}\sin (2\mathrm{\&pi;\&delta;ft}+\mathrm{\&phi;})---\left(6\right)$

[several 7]

${\mathrm{<figure-callout\; id="3"\; label="S"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">S</figure-callout>}}_3=\frac{2i_1}{K_1}-{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">S</figure-callout>}}_1=\frac{4}{\mathrm{\&pi;}}\sqrt{I_s{I}_r}\cos (2\mathrm{\&pi;\&delta;ft}+\mathrm{\&phi;})---\left(7\right)$

As utilize formula (6) and formula (7), then the amplitude of the heterodyne signal shown in the formula (1) is as follows.

[several 8]

$\sqrt{I_s{I}_r}\&Proportional;\sqrt{{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">S</figure-callout>}}_2^2+{\mathrm{<figure-callout\; id="3"\; label="S"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">S</figure-callout>}}_3^2}---\left(8\right)$

Here, the proportionality constant about the right is π/4.Therefore, by using the flip-flop of being asked from formula (5), can calculate the amplitude of heterodyne signal.Therefore, the amplitude of aforesaid flip-flop and heterodyne signal is overlapped, can be in the hope of the intensity of heterodyne signal, i.e. the intensity of interference light L.

By this, 1 pair of optical image-measuring device is difficult to carry out in advance the image instrumentation of bias light strength detection, and for example light faultage image instrumentation of moving object etc. is effective.And, because do not need to measure in advance in addition the intensity of the flip-flop that forms bias light, can seek the simplification of measuring program.Therefore, the trouble on the instrumentation can alleviate, and the instrumentation time also can shorten.

In addition, as utilize optical image-measuring device 1, then can utilize following such assay method to try to achieve the space distribution and the image conversion of the phase place of interference light L.

To certain minute t=t ₁, as obtain the interference light composition S of the heterodyne signal shown in formula (6) and the formula (7) ₂(t ₁) and S ₃(t ₁), then can be by obtaining these two ratios of interfering compositions, and obtain the signal shown in the following formula.

[several 9]

${\mathrm{<figure-callout\; id="4"\; label="S"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">S</figure-callout>}}_4=\frac{S_2\left(t_1\right)}{S_3\left(t_1\right)}=\tan (2\mathrm{\&pi;\&delta;<figure-callout\; id="1"\; label="f\; t"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">f</figure-callout>}{t}_{}{}_1+\mathrm{\&phi;})---\left(9\right)$

By this formula (9) as can be known, signal S ₄Do not exist with ... the amplitude of interference light L, include only its phase information.Therefore, utilizing 2 dimension optical sensor arrays is phase (x, y, the t of the heterodyne signal that each pixel detected and exported of CCD 21,22,23 ₁), be shown below.Here, (x, y) represents each the locations of pixels coordinate on these CCD.

[several 10]

The 2nd the 2 π δ ft of this formula (10) ₁For having zero or be roughly the minute t of the AC signal of zero frequency δ f ₁The instantaneous phase value, can suppose that it is not a certain value according to the location of pixels (being variable x, y) of CCD 21,22,23.Therefore, by to being positioned at certain the coordinate x=x on the CCD 21,22,23 ₁, y=y ₁The phase (x of the heterodyne signal that pixel detected ₁, y ₁, t ₁), and try to achieve the phase differential of the heterodyne signal that each pixel detects.Can make this heterodyne signal, i.e. the space distribution imageization of the phase differential of interference light L.The space distribution of the phase place of this interference light is measured, and is considered to the image instrumentation of its phase value as benchmark, and the high precision instrumentation that for example utilizes the mirrored surface of heterodyne interferometry is effective.

In addition, as utilize above-mentioned phase information, can ask for the frequency information of interference light L.That is the frequency f of heterodyne signal, _IfWith sampling frequency f _SmDifference on the frequency δ f, can utilize according at certain two minute t=t ₁And t=t ₂In the result of calculation φ (x of phase place ₁, y ₁, t ₁) and φ (x ₁, y ₁, t ₂) following formula and calculate.

[several 11]

$\mathrm{\&delta;f}=\frac{1}{2\mathrm{\&pi;}}\left|\frac{\mathrm{\&phi;}\left({x,y,t}_1\right)-\mathrm{\&phi;}\left({x,y,t}_2\right)}{t_1{-\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="A20051005531900301.png"\; state="\{\{state\}\}">t</figure-callout>}}_2}\right|---\left(11\right)$

Because sampling frequency f _SmFor known, so, can calculate the frequency f of heterodyne signal by the resulting result of calculation of formula (11) _If, i.e. the frequency of interference light L.The assay method of this heterodyne frequency is considered to be effectively applied to the situation of the blood flow state on the tested eye of instrumentation eyeground for example etc., so use the multispectral measurement of velocity of reining in of heterodyne interferometry to be utilized effectively.

In addition, in the optical image-measuring device 1 of above-mentioned enforcement kenel, adopted the structure of the dimmer 31,32,33 that possesses high speed dimmer etc., as intensity modulation device of the present invention.But the intensity modulation device is not limited thereto.For example, this dimmer device that interference light is fully interdicted replaces, can periodically increase and decrease the transmitance that allows interference light see through by being provided with, spatial light modulation device (spatial light modulator for example, SLM) etc., the interference light intensity that the optical detection device of CCD etc. is accepted can be carried out modulation, and the sampling interference light.In other words, the shading means are done switching for the interference light intensity that optical detection device is accepted between 0 and 100 (maximum intensity), and intensity modulation device of the present invention is for can use interference light intensity in the structure of for example doing switching between 10 and 80.

Moreover it is switching between 2 numerical value that the intensity modulation of interference light has more than, can be in response to the form of sampling, and adopt between 3 or above numerical value, to do periodically and switch, or 2 numerical value are done periodically and continuous switching mode.In addition, if deciding also, the sensitivity of the width of intensity modulation consideration CCD etc. are fine.If intensity modulation device of the present invention is modulation periodically, adopt which kind of structure all to be fine.The structure of intensity modulation device and being made of one of optical detection device also is fine.

Optical splitter 5,11,12 can use any kenel person, but if the words of the optical splitter of cube type of use (cube), probably can incide among the CCD at the reflected light with the edge joint mouth of air, be more suitable so use the optical splitter of template (plate) or wedge type (wedge) etc.

In addition, in the optical image-measuring device 1, the optical system that the detection system light path that is disposed with lens group 8 etc. by the light path that has adopted the illuminator that lens 3,4 are disposed and imaging is separated, the influence of the reflection that the optical module on each light path produces just is eliminated.

In optical image-measuring device 1, be provided with 3 independent CCD21,22,23, but be to use three pieces of formula CCD cameras (unit) as the colored CCD camera mode of 3CCD type, configuration intensity modulation device on the anterior locations of each CCD chip, the structure of using formation and be in appearance 1 CCD camera also is feasible.By this, can the attempt simplification of apparatus structure and the save spaceization etc. in the device.

In addition, be divided into several zones by the sensitive surface with a CCD, configuration intensity modulation device on each regional anterior locations is made as a CCD with each zone of CCD, also is fine with the structure that detects interference light.At this moment, dispose the intensity modulation device that the liquid crystal SLM etc. of the sizes that those most zones of CCD are covered is constituted, the zone of each regional intensity modulation device of corresponding CCD is controlled respectively, it also is feasible using the detection of carrying out interference light.Utilize this structure, the save spaceization in the simplification of the apparatus structure of can attempting and the device.In addition, because do not need the CCD of majority control synchronized with each other is sampled, can seek the simplification of control system.

Person more is by the skew adjustment of the flip-flop of the electric charge that suitably is accumulated in CCD and the gain adjustment of AC signal, the contrast that can improve the formed interference figure of detected interference light.

In addition, by the inflection mirror of using 2 secondary reflections or angle side's body (corner cube) as the reference object, can reduce z-scanning the time the displacement with reference to object.By this, the save spaceization in the device of can attempting, in addition, also can alleviate add all in making with reference to the burden of the above-mentioned drive unit of movement of objects and consuming the electric power amount.

[the variation example that obtains kenel of the flip-flop of corresponding bias light]

In above-mentioned enforcement kenel, the method that is adopted is by with sampling function m ₁(t) with sampling function m ₂(t) phase differential between is set at Δ θ _1,2=-pi/2, and sampling function m ₁(t) with sampling function m ₃(t) phase differential between is set at Δ θ _1,3=pi/2, obtaining the flip-flop of corresponding bias light, but the kenel that obtains of flip-flop is not limited thereto kind of a mode.Hereinafter, other that flip-flop is described with an example obtained kenel.Change example according to this, the degree of freedom that obtains the framework of flip-flop is enhanced, and the practicality of device also promotes.

(first of the kenel that obtains of flip-flop changes example)

At first, identical with reference to figure 3 with above-mentioned enforcement kenel, illustrate according to 2 electric signals that CCD exported, calculate the method for direct current composition.Below, though by the CCD22 that uses Fig. 1,23 structure, only possess the optical image-measuring device of 2 CCD or the optical image-measuring device that possesses more than 4 also can similarly carry out computing, this needn't speak more.

For this reason, with sampling function m ₂(t) with sampling function m ₃(t) phase differential between is set at Δ θ _2,3=π (180 degree).For example, as shown in Figure 3, sampling function m ₁(t) the sample range L1 ' of interference light L1 is made as 0～π/4, sampling function m ₂(t) the sample range L2 ' of interference light L2 is made as π/4～π/4, sampling function m ₃(t) the sample range L3 ' of interference light L3 be made as 3 π/4～2 π/.At this moment, sampling function m ₁(t) with sampling function m ₂(t) the phase difference θ between _1,2For-pi/2, and sampling function m ₁(t) with sampling function m ₃(t) the phase difference θ between _1,3 Be 3 π/4.Sampling function m ₁(t), m ₂(t) and m ₃(t) become respectively and have the frequency identical with beat frequency.In addition, sampling function m ₁(t), m ₂(t) and m ₃(t) work period is than the work period that is respectively 25%.

Calculation handling part 60 is done time average to CCD22,23 electric signals of being exported when carrying out this sampling, calculate the flip-flop of the bias light of corresponding interference light L.That is, because the phase difference θ of the sample range L3 ' of the sample range L2 ' of interference light L2 and interference light L3 _2,3Be π, by these are done time average, alternating component just is cancelled, and only captures flip-flop i _DThen, according to this flip-flop i _D, obtain the intensity of the direct current composition of purpose.In addition, the setting value Δ θ of the phase differential of above-mentioned enforcement kenel _1,2=-pi/2, and Δ θ _1,3=pi/2 is an example of situation for this reason.

At this, so-called " electric signal is done time average " is meant: will show from the electric signal of CCD (optical detection device) be subjected to the light light quantity, obtain time of a picture frame, the processing that averages with for example this CCD.In addition, be to mean the time average of trying to achieve each electric signal to " time average " of most electric signals, again with the processing of these time averaging mean value vacations to calculate.In addition, having more than in above-mentioned " time " that time average is handled is the time that is defined as 1 picture frame, for example also can adopt sampling period etc. or needed certain hour.

As above-mentioned, by two CCD, be subjected to the phase differential π of interference of light light to do setting respectively, with these two CCD respectively output electric signal do time average, can calculate the flip-flop of the bias light of corresponding interference light L by this.According to the method, also the phase differential of sampling twice interference light can be set as π, because can set the beginning of each sampling and the sequential of end arbitrarily, the degree of freedom that is used for obtaining the mensuration kenel of flip-flop can improve.

In addition, will be each other phase differential be made as π, the electric signal of sampled from correspondence three or above interference light also can similarly be tried to achieve flip-flop.

(second of the kenel that obtains of flip-flop changes example)

Then, illustrate and use one piece of electrical signal that CCD exported, the method for the value of trying to achieve stream composition.At Fig. 4, shown the sampling kenel of this purposes.Below, though adopted the CCD 22 of optical image-measuring device shown in Figure 11, utilize only to possess single CCD or the device of several CCD arbitrarily, also can be in the hope of flip-flop.

In this variation example, utilize CCD22 to carry out most times mensuration, according to these mensuration repeatedly, use electric signal from CCD 22.Therefore, with phase difference θ _2,2The mode of=π is carried out the sampling of the interference light L2 of most times (for example 2 times).For example, two sampling functions of sampling interference light L2 are m ₂(t), n ₂(t), as shown in Figure 4, sampling function m ₂(t) the sample range L2 ' of interference light L2 is made as π/4～pi/2, sampling function n ₂(t) the sample range L2 of interference light L2 " be made as 3 π/4～2 π.Sampling function m ₂(t), n ₂(t) be made as respectively and have the frequency identical with beat frequency.In addition, sampling function m ₂(t), n ₂(t) work period is than the work period that is respectively 25%.

Calculation handling part 60 is done time average to the electric signal that CCD 22 is exported when carrying out this sampling, calculate the flip-flop of the bias light of corresponding interference light L.That is, because the sample range L2 ' of interference light L2 and L2 " phase difference θ _2,2Be π, by these are done time average, alternating component just is cancelled, and only captures flip-flop i _DThen, according to this flip-flop i _D, obtain the intensity of the direct current composition of purpose.

As mentioned above, phase differential with each sampling is π, interference light on the same light path is done twice sampling, will from the single CCD on this single light path the electric signals of indivedual outputs carry out time average, can calculate the flip-flop of the bias light of corresponding interference light L by this.According to the method, will do the phase differential in twice when sampling to interference light is π, because can set the beginning of each sampling and the sequential of end arbitrarily, the degree of freedom that is used for obtaining the mensuration kenel of flip-flop can improve.In addition, only possess the device of a CCD, also can measure flip-flop effectively.

In addition, will be each other phase differential be made as π, the electric signal of sampled from correspondence three or above interference light also can similarly be tried to achieve flip-flop.For example, when sampling with the frequency of the even-multiple of beat frequency, according to the electric signal that CCD exported, can be in the hope of flip-flop.In addition, if in the accumulated time of CCD, the structure that cooperates beat frequency to carry out most times sampling becomes the intensity that shows flip-flop this moment from the electric signal that CCD exported.Also can try to achieve the intensity of flip-flop according to this signal.

(the 3rd of the kenel that obtains of flip-flop changes example)

Then explanation obtain the flip-flop that bias light constitutes kenel the 3rd change example.It is identical that this variation example and second changes example, for only using a CCD (for example CCD 22) person.Therefore, with sampling frequency m ₂(t) set frequency (beat frequency) f with heterodyne signal for _IfAsynchronous.Like this different part of phase place of interference light can successively be sampled, and (almost) of interference light full phase range 0～2 π is sampled as a result.Therefore, by sampling results is done time average, alternating component just is eliminated, and only takes out flip-flop.

With reference to figure 5, an example of this variation example is described.At this, the periodic table of heterodyne signal is shown T ₀=1/f _If, be expressed as T=1/f sampling period.In addition, ratio is set at 40% the work period of sampling.Sampling frequency f is set at beat frequency f _IfNumerical value (f=0.8 * f of 0.8 times _If), sampling period, T became the period T of heterodyne signal ₀1.25 times of (T=1.25 * T ₀).At this moment, the first sample range L2 (1) is corresponding to the part of the phase place 0～π of interference light, the second sample range L2 (2) is corresponding to the part of phase place pi/2～3 pi/2s of interference light, the 3rd sample range L2 (3) is corresponding to the part of phase place π～2 π of interference light, and the 4th sample range L2 (4) is corresponding to the part (following identical) of the phase place 3 pi/2s～pi/2 of interference light.According to such sampling, because interference light is all sampled at whole section phase place 0～2 π, by sampling results is done time average, alternating component is eliminated, and captures flip-flop i _D

In addition, sampling period T setting value had better not be set at the period T of heterodyne signal ₀The value of integral multiple.That is, T=n * T ₀Under the situation of (n is an integer), interference light L2 n under the cycle same phase range sampled, so, also can't eliminate flip-flop even get time average.But if the work period ratio is made as k/n (k is the following integer of n), the k cycle of interference light L2 can be because become each sample range, so can be suitable for.

(the 4th of the kenel that obtains of flip-flop changes example)

Then, at this during, can change example according to the following the 4th, obtain flip-flop with the situation of the framework of optical image-measuring device 1 ' shown in Figure 6.With the optical image-measuring device shown in the figure 1 ' is that remainder then possesses the framework identical with the optical image-measuring device of Fig. 1 at the anterior locations of CCD 23 configuration intensity modulation device (dimmer 33).

When CCD 21,22 detected interference light L1, the L2 that is sampled, the CCD 23 of this optical image-measuring device 1 ' received interference light L3 continuously, converts thereof into electric signal, outputs to signal processing part 60.Signal processing part 60 can only take out flip-flop by carrying out time average from the electric signal of CCD 23.That is because received continuously interference light L3 is a signal at random, to get its time average so utilize, and can eliminate alternating component, takes out flip-flop effectively.In addition,, for example use method that the present inventor's above-mentioned patent document 1 puts down in writing etc., according to trying to achieve from the electric signal of CCD 21,22 about alternating component.As above-mentioned, to the electric signal of the optical detection device on the light path that the intensity modulation device never is set, averaging processing by this can be in the hope of the flip-flop that bias light constituted of interference light.

According to this optical image-measuring device because the flip-flop that bias light constituted that the difference that can have no time is tried to achieve interference light with and alternating component, so the instrumentation time can shorten etc., the convenience of device is also promoted.In addition, because the needed intensity modulation device of apparatus structure is finished with two, the simplification of structure or cost degradation more can be sought the space savingization in the device.Moreover, because 2 CCD and 2 intensity modulation devices can synchro control, so the simplification that can seek to control.Moreover, because see through the intensity modulation device, from the testing result of two interference lights receiving, can be in the hope of alternating component, so the shortening of calculation time can be expected.

In the structure of Fig. 6, CCD 23 is for being used for obtaining the dedicated optical pick-up unit of background light intensity, and its place ahead is not provided with the intensity modulation device.Being suitable for the occasion of this structure, inciding the light quantity of the interference light L3 of CCD 23, also can be the faint amount of several number percent degree of interference light for example.That is, do gain adjustment from the electric signal of CCD 23 with signal processing part 60, the words that perform calculations again are just very abundant.Therefore, carry under this situation with this framework, the ratio of division of the interference light intensity of optical splitter 12 be not 1: 1 also passable.In structure shown in Figure 6, the penetrance of optical splitter 12 can be set for the value littler than reflectivity.

(the 5th of the kenel that obtains of flip-flop changes example)

At last, illustrate that changes an example, it for example switches the light-receiving time of the interference light of optical detection device with periodicity mode, the sampling action of control intensity modulation device can calculate the flip-flop corresponding to the bias light of interference light by this one by one.

Fig. 7 is the sampling kenel that is presented at this variation example.In this variation example, by dimmer 31, the interference light L1 that samples, in addition, the cycle of sampling is set as the period T with heterodyne signal ₀Synchronously.In addition, dimmer 31 is for constituting the alleged light-receiving time switching device shifter of the present invention.Sample range at the beginning is the L1 (1) that was set as for 1 cycle, and second is the L1 (2) of semiperiod, and the 3rd is the L1 (3) in 1 cycle, and the 4th is the L1 (4) of semiperiod ...., the rest may be inferred by analogy.That is the work period of the sampling function of this variation example is done mutual switching between the work period of work period of 100% and 50%, the person that for example has the square waveform.

Sample according to such sampling function, the sample range L1 (1) of phase place 0～2 π of interference light L1, L1 (3), L1 (5) ..., and the sample range L1 (2) of phase place 0～π of interference light L1, L1 (4), L1 (6) ... both are alternatively received by CCD 21 each other.At this moment, in interference light L1 odd number sample range and even number sample range, the ratio of the light-receiving time of CCD 21 becomes 2: 1.CCD 21 is subjected to the electric signal of each sample range of light with correspondence, is sent to signal processing part 60 in regular turn.

Signal processing part 60 calculate sample range L1 (1), L1 (3) corresponding to odd number, L1 (5) ... the time average of the electric signal that waits, calculate out the flip-flop i that bias light constituted of interference light by this _DThis is that the phase place of several sample ranges of ground is 0～2 π, and just 1 cycle, so get its time averaging words, alternating component is eliminated, and is able to according to the flip-flop that captures.

In addition, signal processing part 60 calculates the amplitude and the phase place of alternating component according to the intensity of each electric signal of each sample range of corresponding even number, and the flip-flop that electric signal electric signal that exported from CCD 22 and/or CCD 23 and corresponding odd number sample range before it is calculated synchronous with it.

At present embodiment, the calculating of this flip-flop of mutual in regular turn execution and the calculating of alternating component.Therefore, for example utilizing z-scanning, on one side when changing the degree of depth of determined object O and carrying out the situation of instrumentation, can calculate the intensity of the flip-flop of each degree of depth of (almost) correspondence one by one, according to this result of calculation, can be in the hope of alternating component.Therefore, the instrumentation degree of accuracy of each degree of depth of determinand O just is enhanced.

In addition, in the computing of alternating component, according to the time from the situation of the output signal of 3 CCD, can use the computing method of for example above-mentioned enforcement kenel etc., in addition, according to the time, can use method that for example above-mentioned patent document 1 puts down in writing etc. from the situation of the output signal of 2 CCD.

Calculating the sampling that flip-flop uses can carry out with 1 cycle, also can carry out with for example arbitrary sequence in 2 cycles, 3 cycles etc.For example being initially for 1 cycle, then was 2 cycles ... etc., the interval of change sampling also is fine.

In addition, as the light-receiving time switching device shifter, except the dimmer device that interference light is covered fully, the intensity modulation device of use SLM etc. also can.

As above-mentioned, this variation example is switched for the length of the light-receiving time of the interference light that carries out optical detection device, when long light-receiving time (first light-receiving time), ask for flip-flop according to the electric signal that optical detection device is exported, and electric signal of being exported during according to short light-receiving time (second light-receiving time) and the flip-flop of being tried to achieve are tried to achieve alternating component.At this, first light-receiving time is to eliminate alternating component in order to handle with equalization, for the time (for example integral multiple in the cycle of beat frequency) of the length more than the beat period of interference light, better is the cycle that equals this beat frequency.In addition, second light-receiving time is the time less than the length of the beat period of interference light, better is half of cycle that equals this beat frequency.That is the work period ratio that utilization will be used for obtaining the sampling of alternating component is set as 50%, can carry out instrumentation effectively.

[the variation example of sampling kenel]

Then, an example of the sampling kenel that optical image-measuring device of the present invention is described is suitable for.Particularly illustrate relevant for the frequency, work period of sampling variation example than the waveform of, sampling function etc.According to following variation example, the degree of freedom of sampling kenel can improve, and the practicality of device also can promote.

(about sampling frequency)

In the above-described embodiments, sample with sampling frequency rough and that beat frequency equates, but be not limited thereto.For example, use the beat frequency of interference light, promptly the frequency of beat frequency integral multiple can periodically distinctly be sampled to a plurality of phase range of interference light as sampling frequency.According to this kind method, because can a sampling population phase range in each cycle of interference light, so can analyze interference light in more detail, the lifting of instrumentation precision also can be expected.

On the other hand, can use integer/one's times (1/n) of beat frequency sampling frequency.According to the method, because the predetermined phase scope of interference light is to sample with the n cycle, so when the intensity switching of intensity modulation device can't catch up with the situation of beat frequency, also can effectively utilize.

(about the work period ratio)

The employed sampling function of optical image-measuring device of the present invention better was to use for 50% work period.That is less than 50% work period the time, CCD 21,22,23 light quantities of being accepted can reduce, and the detection efficiency of interference light can reduce.On the other hand, when surpassing for 50% work period, detection efficiency also can reduce.But, when the sampling of carrying out shown in above-mentioned Fig. 3-5, can use suitable and required work period ratio.

(about the waveform of sampling function)

In addition,, be preferably and use square waveform shown in Figure 2, come the switching sequence of dimmer 31,32,33 is done suitably switching as the employed sampling function of light image device of the present invention.But, also can be suitable for the sampling function that waveform constituted beyond the rectangle of sine wave or triangular wave etc.Particularly, during intensity modulation device beyond the shade of the switching that penetrates Yu interdict of interference light is carried out in use, can use the waveform beyond the rectangle effectively.For example, the sampling function by using sinusoidal or triangular waveform makes the penetrance of intensity modulation device do continuous variation, and the interference light intensity that penetrates is carried out modulation, continuously the interference light intensity that received of modulation CCD.

In addition, the sampling function of use sine wave etc. can be carried out the sample process identical with the square waveform sampling function.For example, can the frequency of utilization response high optical diode etc. are sinusoidal waveform detected bat signal is tentative, use this signal to control the sampling of interference light.Specifically, for example with the peak swing of detected bat signal ± 1/ √ 2 is set at critical value, at the time point of corresponding this critical value, moment ground switch the on/off of dimmer.At this moment, the phase place π of interference light/4～3 π/4 parts and 5 π/4～7 π/4 parts are sampled, and the work period ratio is 50%, and sampling frequency is 2 multiple value of beat frequency.In addition, aforementioned critical value is not limited to ± 1/ √ 2, can set arbitrary value arbitrarily for.In addition, switching at the on/off of the dimmer in 1 cycle of clapping signal also can be beyond 4 times.By suitably changing above-mentioned critical value, the light quantity of the interference light that CCD accepts is at random adjusted.An example as this light quantity corrective action, as scheme shown in the light portrait shown in Figure 1, when interference light being divided into most light paths with the situation that detects, because the penetrance of each optical splitter or the influence of reflectivity etc., the light quantity of interference light has the situation that can't on average cut apart; But by the relevant aforementioned critical value of the control of the dimmer on each light path is suitably adjusted, the light quantity that each CCD accepted just can equalization.

In addition, by using sine-shaped sampling function,,, the response speed of the optical detection device of CCD etc. also can reach accordingly so promoting because the lifting of the calculation processing speed relevant with Fourier analysis can be expected.

(other variation example)

Below other of the optical image-measuring device 1 of the above-mentioned enforcement kenel of explanation changes example.At first, it is general that optical image-measuring device of the present invention is not limited to the foregoing description, and interference light is divided into the structure of 3 light paths, and as described in the explanation of the variation example that obtains kenel in flip-flop, the number that is used for detecting the light path of interference light is arbitrarily.When being divided into the situation of most light paths, general as shown in Figure 6, the optical detection device of CCD etc. is set on each light path, and the intensity modulation device of dimmer etc. is set on the light path beyond the light path, or also the intensity modulation device can be set on all light paths.But, can adopt in divided most light paths according to assay method or calculation method, the intensity modulation Design of device is set.

And, as optical detection device, outside the above-mentioned CCD 21,22,23, also can use the line sensor that possesses the calculation circuit about optical image-measuring device of the present invention.Optical detection device of the present invention has the function of accepting interference light and carrying out opto-electronic conversion, and accumulates these two of functions that detect electric charge according to the interference light of accepting, and can be used on all formations of 1 dimension or 2 dimensions.

In example of the present invention discussed above, be that optical image-measuring device to interference optics with inferior type of Mike (Michelson) is illustrated, but also can adopt Mach-zehnder type (Mach-Zehuder) for example to wait other interference optics (for example, with reference to aforementioned patent shelves 2) certainly.

And, use as light conducting member by optical fiber (bundle) is set on the part of interference optics, can improve the degree of freedom in the device design, or the simplicity (compact) of seeking device, or improve the configuration degree of freedom (for example, with reference to aforementioned patent shelves 2) of determined object.

On the field that optical image-measuring device of the present invention is applied in ophthalmology for example, then except the mensuration of the blood flow state on above-mentioned eyeground, also can obtain 2 dimension cross-section images of nethike embrane or cornea etc.By this, can measure endothelial cell number of for example cornea etc.In addition, certainly also can carry out other various application beyond medical or industrial etc.

The above formation that describes in detail only about an example of the example of optical image-measuring device of the present invention, as long as in the scope of main idea of the present invention, can apply various distortion.

The above, it only is preferred embodiment of the present invention, be not that the present invention is done any pro forma restriction, though the present invention discloses as above with preferred embodiment, yet be not in order to limit the present invention, any those skilled in the art, in not breaking away from the technical solution of the present invention scope, when the technology contents that can utilize above-mentioned announcement is made a little change or is modified to the equivalent embodiment of equivalent variations, in every case be the content that does not break away from technical solution of the present invention, according to technical spirit of the present invention to any simple modification that above embodiment did, equivalent variations and modification all still belong in the scope of technical solution of the present invention.

Claims (12)

1, a kind of optical image-measuring device, have light source and interference optics, wherein light source is used for outgoing beam, interference optics is used for the light beam from this light source, be divided into via the flashlight of object to be detected and via set with reference to object with reference to light, and make aforementioned signal light frequency with aforementioned with reference to light frequency is relative carry out displacement after, make via aforementioned object to be detected aforementioned flashlight and via aforementionedly carrying out overlapping each other with reference to light with reference to the aforementioned of object, and the generation interference light, and this optical image-measuring device forms the image of aforementioned determined object according to aforementioned interference light, it is characterized in that it comprises:

The intensity modulation device is with the predetermined aforementioned interference light intensity of frequency modulating;

Optical detection device is accepted by the aforementioned interference light of aforementioned intensity modulation, is transformed into electric signal and with its output; And

Calculation apparatus, according to the aforementioned electric signal from aforementioned optical detection device output, calculation is by the intensity of the flip-flop that bias light constituted of aforementioned interference light.

2, a kind of optical image-measuring device has light source, interference optics and beam-divider means, and wherein light source is used for outgoing beam; Interference optics is used for the light beam from this light source, be divided into via the flashlight of object to be detected and via set with reference to object with reference to light, and make aforementioned signal light frequency with aforementioned with reference to light frequency is relative carry out displacement after, make via aforementioned object to be detected aforementioned flashlight and via aforementionedly carrying out overlappingly each other with reference to light with reference to object aforementioned, and generate interference light; The aforementioned interference light that beam-divider means generates aforementioned interference optics is divided into most light paths, wherein this optical image-measuring device is according to the aforementioned interference light that transmits in an aforementioned majority light path, form the image of aforementioned determined object, it is characterized in that it comprises:

A most intensity modulation device are separately positioned on the wherein several light path in the aforementioned majority light path, with the predetermined aforementioned interference light intensity of frequency modulating;

A most optical detection device, be separately positioned on the aforementioned majority light path, the aforementioned lights pick-up unit that wherein is arranged on wherein several light paths of an aforementioned majority light path is to accept by the aforementioned interference light of aforementioned intensity modulation, be transformed into electric signal and with its output, and be arranged on aforementioned lights pick-up unit beyond wherein several light paths of an aforementioned majority light path for accepting aforementioned interference light, be transformed into electric signal and with its output; And

Calculation apparatus, according to the aforementioned electric signal that the aforementioned lights pick-up unit on the predetermined light paths from be arranged on an aforementioned majority light path is exported, calculation is by the intensity of aforementioned flip-flop.

3, optical image-measuring device according to claim 2, it is characterized in that wherein said predetermined light paths comprises at least two light paths that aforementioned intensity modulation device is set up, aforementioned intensity modulation device on aforementioned at least two light paths is the aforementioned interference light of modulation respectively, the phase differential that makes aforementioned lights pick-up unit on this light path accept aforementioned interference light is the part of π (180 degree), and aforementioned calculation apparatus carries out time average by the aforementioned electric signal that the aforementioned lights pick-up unit is exported, and calculates out the intensity of aforementioned flip-flop.

4, optical image-measuring device according to claim 2, it is characterized in that wherein said predetermined light paths comprises the light path that aforementioned intensity modulation device is not set up, aforementioned calculation apparatus carries out time average by the aforementioned electric signal that the aforementioned lights pick-up unit is exported, and calculates out the intensity of aforementioned flip-flop.

5, optical image-measuring device according to claim 1 and 2 is characterized in that wherein said intensity modulation device carries out majority time intensity modulation to aforementioned interference light, and the phase differential that makes the aforementioned lights pick-up unit accept aforementioned interference light is the part of π;

The aforementioned lights pick-up unit is accepted and the inferior corresponding aforementioned interference light of each time intensity modulation of aforementioned majority, the output electric signal;

The corresponding aforementioned several intensity modulation of aforementioned calculation apparatus carries out time average by the aforementioned electric signal that the aforementioned lights pick-up unit is exported, and calculates out the intensity of aforementioned flip-flop.

6, optical image-measuring device according to claim 1 and 2, it is characterized in that wherein said intensity modulation device is to utilize not and the synchronous frequency beat period of aforementioned interference light, aforementioned interference light is carried out intensity modulation, and aforementioned calculation apparatus is according to the aforementioned interference light of doing the intensity modulation with this frequency, carry out time average by the aforementioned electric signal that the aforementioned lights pick-up unit is exported, calculate out the intensity of aforementioned flip-flop.

7, a kind of optical image-measuring device, have light source and interference optics, wherein light source is used for outgoing beam, interference optics is used for the light beam from this light source, be divided into via the flashlight of object to be detected and via set with reference to object with reference to light, and make aforementioned signal light frequency with aforementioned with reference to light frequency is relative carry out displacement after, make via aforementioned object to be detected aforementioned flashlight and via aforementionedly carrying out overlapping each other with reference to light with reference to the aforementioned of object, and the generation interference light, and this optical image-measuring device forms the image of aforementioned determined object according to aforementioned interference light, it is characterized in that it comprises:

The intensity modulation device is with the predetermined aforementioned interference light intensity of frequency modulating;

Optical detection device is accepted by the aforementioned interference light of aforementioned intensity modulation, is transformed into electric signal and with its output; And

Calculation apparatus, according to the aforementioned electric signal from aforementioned optical detection device output, calculation is by the intensity of the flip-flop that bias light constituted of aforementioned interference light, and the intensity and/or the phase place of calculation alternating component.

8, optical image-measuring device according to claim 7, it is characterized in that more comprising a light-receiving time switch means, the cycle of the beat frequency of corresponding aforementioned interference light, the light-receiving time of the aforementioned interference light of aforementioned lights pick-up unit is switched between one first light-receiving time and one second light-receiving time, wherein aforementioned first light-receiving time has the above length of cycle of aforementioned beat frequency, and aforementioned second light-receiving time has the length less than the cycle of aforementioned beat frequency

Wherein aforementioned calculation apparatus is former when stating the light-receiving time switching device shifter and switching to aforementioned first light-receiving time, carry out time average by the electric signal that the aforementioned lights pick-up unit is exported, calculate out the intensity of aforementioned flip-flop, and when switching to aforementioned second light-receiving time, the aforementioned electric signal of being exported according to the aforementioned lights pick-up unit, and corresponding aforementioned first light-receiving time and the aforementioned flip-flop calculated out, calculate out the intensity and/or the phase place of aforementioned alternating component.

9, optical image-measuring device according to claim 8 is characterized in that wherein said light-receiving time switching device shifter switches aforementioned light-receiving time with the cycle of the beat frequency of every aforementioned interference light, and aforementioned first light-receiving time is aforementioned beat period.

10, optical image-measuring device according to claim 8, it is characterized in that wherein said light-receiving time switching device shifter switches aforementioned light-receiving time with the cycle of the beat frequency of every aforementioned interference light, aforementioned second light-receiving time is half of aforementioned beat period.

11, optical image-measuring device according to claim 7 is characterized in that aforementioned preset frequency that wherein said intensity modulation device carries out intensity modulation to aforementioned interference light is the frequency of integral multiple of the beat frequency of aforementioned interference light.

12,, it is characterized in that wherein said intensity modulation device is the dimmer device, with aforementioned predetermined frequency, interdicts aforementioned interference light according to the described optical image-measuring device of arbitrary claim in the claim 1 to 11.

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